CR-Chord: Improving lookup availability in the presence of malicious DHT nodes

Distributed Hash Tables (DHTs) provide a useful key-to-value lookup service for many Internet applications. However, without additional mechanisms DHTs are vulnerable to attacks. In particular, previous research showed that Chord is not well resistant to malicious nodes that joined the DHT. We introduce the cyclic routing algorithm as an extension of Chord (CR-Chord). Using simulations we compare the lookup availability of Chord and CR-Chord. The results suggest that CR-Chord improves the lookup availability on the average by 1.4 times. When the number of malicious nodes is small, such as 5%, CR-Chord has almost twice lower lookup failure rate.